Insulator



Oct. 14, 1930. c. s. VAN ATTA INSULATOR Filed May 4, 1,925

Patented Oct. 14, 1930 UNITED STATES PATENT OFFICE OLOYD B. VAN ATTA, BALTIMORE, MARYLAND, ASSIGNOR TO LOCKE INSULATOB CORPORATION, OF BALTIMORE, MARYLAND, A CORPORATION OF MARYLAND INSULA'JJOB Application Med May 4, 1826. Serial No. 108,862.

The invention relates to insulators.

The principal object of the invention, generally stated, is to provide means in an insulator of the type embodying metallic and porcelain or other dielectric elements, for pre-.

'used for securing the cap in place and these forces are communicated to the porcelain body resulting in cracking and destruction thereof. To avoid this it has been contemplated to use a bituminous coating, or other non met'allic and non-cementitious substance interposed between the cap and the cement engaged thereby. In the course of time it probabl occurs that a certain amount of this materiai is absorbed into the cement and especially if the cap is out of round, as many are, the'gradual working away of the fluent material from the high spots of the cap, or of the cement, permits contact. As the cap and cement are both very hard, the strain is communicated to the porcelain, with damage thereto.

It is with the above facts in view that I have designed the present invention which has for an im ortant object the provision of means whereby this action will be avoided, the invention contemplating the rovision of a ieldable or ductile and pre erably metallic lining or surface on the insulator cap or its equivalent, this soft area accommodating itself to the cement or other surface without bringing severe strains upon the cement and hence the porcelain or other dielectric material of which the insulator is formed.

A more specific object of the invention is to provide a sleeve, liner or other insert which ma be formed in one or a number of ieces an held in place by any suitable or pre erred means and located at points or areas where the strain is or is likely to become severe.

Still another object-0f the invention is to provide an insulator of the cap and pin or of some other type, the differences being immaterial in which the cap and the pin, or both, may be provided with ductile or ieldable coatings, areas or portions where t e strain occurs so that the usual crushing forces will be eliminated.

Yet another object of the invention is the provision of an insulator in which the cap may be equipped with a soft insert, preferably metallic, capable of being either secured in place or cast or molded into a suitable portion of the cap, or other element, it bein preferable that actual securing be provided so as to avoid displacement during handling prior to assembling.

A still further object of the invention is to provide a cap construction which may be made in the usual manner andof the customary material with the addition of the soft metal insert at any and all necessary points or areas, it being conceivable that the insert or other metallic portion may be roughened, knurled, scored or otherwise treated to rovide a gri for the cement or other bon or for any ot er purpose.

Another object of the invention is to rovide an insulator of this character in'w ich the use of a bituminous coating either for the pin or the cement may be eliminated without sacrificing beneficial results.

An additional object is to provide an insu-,

lator of this type and possessing these characteristics which will be inexpensive to manufacture, as easy to assemble as the ordinary variety, positive in action, efiicient and durable in service, and a general improvement in the art.

With the above and other objects and advantages in view, the invention consists in the details of construction and arrangement of arts to be hereinafter more fully descri ed and claimed, and illustrated in the accompanying drawing in which I Figure 1 is a sectional view through an insulator constructed in accordance with the invention, this view illustrating one possibility, and- Figure 2 is a sectional view showing a form of the invention in which the soft material may be applied in some other manner other than by molding or casting.

Referring more particularly to the drawings, the numeral 1 designates the porecelain body of an insulator which is here shown as of the cap and pintype, though it should be distinctly understood that this is simply for illustrative purposes inasmuch as the invention isequally well adapted for use in connection with insulators of entirely different types, the important feature being the provision of a relatively soft and ductile and 'preferably metallic member located in the cap or upon the pin or in or upon any equivalent or similar portion. In the present instance, the insulator body 1 is shown as having a neck portion 2 upon which is secured the cap 3. In insulators of this type it is generally customary to sand, score or otherwise roughen the neck so as to afford a proper grip for the cement or other binder 4 go which holds the cap in place. It is also known that it is frequently the practice to use an asphaltum-like,'. bituminous or other composition or material which is flowed or coated onto the pin and cap not only for the purpose :5 of effecting a slightly yielding connection but also for excluding moisture at the joints. In viewof the fact that the caps are frequently out of round, it is clear that the fluent material may creep from the high spots so that 80 crushing strains are produced at the areas of engagement of the cap with the neck or the pin within the neck. To obviate this. I have found it expedient to provide a soft and preferably metal area or portion 5 in the cap at 85 the places or areas where the principal strains and stresses occur.

While it is conceivable that this relatively soft metal area may be applied in various different ways, I have, in Figure 1, disclosed a method of application involvingthe molding or casting of the soft metal within a groove of suitablesize and cross section initially formed in the cap as at the lip 6 thereof, the idea being that the groove be of such cross sectional configuration that whenthe "soft metal is cast will be no possibility of displacement. While the shape disclosedis more or less of a dovetailed nature, it should be distinctly under-, stood that there are no limitationsin this respect and while it is true that the soft area may be continuous about the'cap, I do not I to be limited to such an arrangement as it is possible to provide soft metal at any desired spaced points to perform the samefunction.

In Figure 2 I have-shown a form of the invention in which there is provided a soft metal insert 7 fitted within a preferably cor.-

cap, it being clear that this insertmay be pressed, brazed or welded into place orotherwise mounted and that it may be secured by auxiliary means, if necessary. The insert, sleeve or maybe of'any size desired,

.ly exerted thereby. Clearly,

or molded therein there.

.claim respondingly shaped groove or recess in the and may be continuous or formed of parts and sections contacting or spaced apart- If The invention also contemplates the provision of a soft metallic coating 8 for the pin 9 so as to avoid the crushing strains ordinarithe coating for the pin may be provided by dipping the pin into molten metal or by placing a metallic alloy, cement or other equivalent material upon the pin, the mode of application being immaterial. The soft metal may be any suitable alloy havin substantially the physical characteristics of annealed copper in point of hardness, etc., it being conceivable that Babbitt metal of certain grades would be suitable for the purpose.

I have discovered that an insulator constructed in accordance with the invention and provided with a lined cap and coated pin, either or both, possesses unusual durability for the reason that strains and stresses which are practically bound .to occur take place or are present at the areas where the soft metal is provided, this metal having sufficient ductility that it may flow or accommodate itself to surface irregularities or points of distortion. A .Very important feature of the invention is that the casting of the soft metal liner will permit of producing a concentric bearing surface without it being necessary to go through the expensive operation of machinin the cap. The cap may replace one of the or inary variety and may be applied in the same way and secured by the usual cement or other bond. Obviousl the body of the insulator may be formed of some suitable material other than porcelain.

While I have shown and described .a preferred embodiment of the invention, it should be understood that I reserve the right to make such changes in-the form construction and arrangement of parts as Wlll not depart from the spirit of theinvention or the scope of the claims hereunto appended.

Having thus escribed the invention, 1':

1. In an insulator including a porcelain body and a suspension'cap cemented thereto, a soft metal liner within the cap at the area or points of strain with respect to'the cement. 2. Ina suspension insulator, a porcelain body, a cap cemented thereto, and an insert of ductile metal within the cap at the points or areas of strain against the cement.

3. In a suspension insulator having a capthereon and cemented thereto, an insert of ductile metal within the cap at the points and areas of strain between the same and the cement, the cap being grooved for the accommodation of the;

4. In an insulator including a fofclain body having a metal cap cemente thereto,

a yleldable metal linin within, the cap at the points and areas'o strain against the cement.

In testimony whereoi I afiix my signature.

CLOYD B. VAN ATTA. 

